class Program
{
static void Main(string[] args)
{
    string src = @"C:\Users\Administrator\Downloads\";
    string dest = "d:\\test\\dest";
    moveFiles(src, dest); // src -> dest
    Console.WriteLine("image copy finished!");
    Console.ReadLine();
}

/// <summary>
/// 移动文件夹中文件到文件到另一个文件夹
/// </summary>
/// <param name="srcFolder">源文件夹(全路径名)</param>
/// <param name="destFolder">目标文件夹</param>
private static void moveFiles(string srcFolder, string destFolder)
{
    DirectoryInfo directoryInfo = new DirectoryInfo(srcFolder);
    FileInfo[] files = directoryInfo.GetFiles();

    if (!Directory.Exists(destFolder))
    {
        //目标目录不存在则创建  
        try
        {
            Directory.CreateDirectory(destFolder);
        }
        catch (Exception ex)
        {
            throw new Exception("创建目标目录失败：" + ex.Message);
        }
    }

    foreach (FileInfo file in files) 
    {
        if (file.Extension == ".jpg")
        {
            file.MoveTo(Path.Combine(destFolder,file.Name));
        }
    }
}
